Internal expansion engine



Sept. 3, 1940. w. T. KlNsLow INTERNAL EXPANSIN lENGINE Filed July 18, 1958 2 Sheets-Sheet l Sept- 3, 1940. w. T. .NSLOW' v 2,213,816

INTERNAL ExPANsIoN ENGINE Filed July 1a, 193s 2 sheets-sheet 2 W41. rse 7.' /OMs-ow di l'o: manif Patented Sept. 3, 1940 UNITE. ST'WE,

.anni

4 Claims.

Tl'ns invention relates to internal uid expansion engines and has particular utility 'when embodied with an internal combustion engine.

In internal fluid expansion engines and particularly in internal combustion engines the impulse of an expanding charge of gas under high pressure is applied to the piston when the latter is practically on dead center. The moments by which the force of the explosion are applied to rotation of the crank shaft are at this time at their minimum. The full effect of the explosion is not applied to the crank shaft therefore until much of the power developed in the explosion been dissipated by expansion of the com.- bustion gases.

It is an object of my invention to provide an internal iiuid expansion engine in which the energy of the expanding charge is more eiiiciently applied to the rotation of the crank shaft thereby increasing the power of the engine and the efficiency with which fuel is utilized thereby.

The manner of accomplishing this object as well as further objects and advantages will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. l is a diagrammatic cross-sectional View of an internal combustion engine comprising a preferred embodiment of my invention and illustrating the parts thereof positioned as at the moment of firing.

Fig. 2 is a longitudinal sectional view taken on the line 2 2 of Fig. l.

Fig. 3 is a horizontal cross-sectional view taken on the line 3 3 of Fig. l and illustrating the intake ports and Valve of the engine.

Fig. ll is a diagrammatic operation View illustrating the parts of the engine at the moment of exhausting.

Fig. 5 is a view similar to Fig. 4 illustrating the parts of the engine at the moment of intake.

Fig. 6 is a view similar to Fig. 5 and illustrates the compression stroke of the engine.

Fig. 7 illustrates the position of the parts of the engine just prior to the moment of firing.

Referring specifically to the drawings, the engine comprising the preferred embodiment of my invention will be designated by the numeral lll. This includes a crank case Il in which is rotatably journalled a crank shaft l2 having two cylinder crank pins i3 and a piston crank pin lll. Mounted on the crank case l l is a water jacketed block I5 having a cylindrical bore l5 in which a hollow cylinder ll is slidably disposed. The block i5 has an intake passage 20 which con- (Cl. 12S-50) nects through a series of ports 2l with the bore l5, as shown in Figs. l and 3. The block has mounted thereon an intake pipe 22, the inner end of which communicates with the passage 2i? and carries a flat check valve 23 which seats on the inner end of the pipe Z2 and is yieldably held in closed position by a spring 255. This` spring bears against an apertured guide bar 25 through which the stein of thevalve 23 passes and by which it is slidably guided.

The block l5 also has a threaded recess 3@ which connects through a port di with the sleeve bore W, said recess being adapted to receive a spark plug 32. A suitable ignition system (not shown) is provided for firing this plug 32 in proper timed relation with the rotation of the shaft l2 as will be made clear hereinafter.

Also formed in the block l5 is a series of eX- haust ports 35 which open into the block bore it and connect outwardly with an exhaust pipe provided on the block.

The cylinder il' is pivotally connected by connecting rods 3i' to the crank pins i3 as shown in Figs. l and 2 so that rotation of the shaft is accompanied by the reciprocation of the cylinder il and the sleeve bore it?. This cylinder has a head il@ and a cylinder chamber di. Provided in the cylinder ll is a series of intake ports di which register with the intake ports 2l of the block l5 when these ports are on the same level as shown in. Figs. 3 and 5. The cylinder Il also has a ring port i3 which registers with the spark plug port 3l when these ports are on the same level as shown in Fig. l. The cylinder il also has a series of exhaust ports 55 which register with the exhaust ports 35 when these ports are on the same level as shown in Fig. 4. The cylinder il is also provided with a pair of compression rings #i6 disposed above and below the ports ft2 and 1.3.

Slidably disposed in the cylinder chamber tl is a piston 5t having compression rings 5l and connected by a connecting rod 52 to crank pin i4 so that reciprocation of the piston 5@ in the cylinder chamber M imparts rotation to the shaft Operation 45 The engine iii of my invention is preferably of the two cycle type in which a charge of fuel is iired during each revolution of the shaft l2. Fig.

l shows the engine at the point of ring in which 5 a charge of fuel compressed between the piston E and the cylinder head ifi is red by the spark plug 32 through the ports 3l and E3 which are here in registry. It is to be noted that this firing takes place with the piston crank pin I4 dis- 55 lss posed at an angle of approximately 45 degrees past dead center.` The power of explosion when this is at its maximum is thus applied to the crank pin li when the latter is so disposed that the torque moments with which this power is applied to the crank shaft I2 are substantially at their maximum. In other words, the expansive force of the explosion in the cylinder il is given the greatest leverage on the shaft l2 when this expansive force is at its peak.

The operation of the engine lil so as to eiTect this result is as follows:

Figs. 4, 5, 6 and 7 show successive situations in a single revolution of the shaft i2 beginning with the ring position as shown in Fig. 1 and ending up just prior to reaching the next firing position.

Fig. 4 shows the piston 50 after it has moved downwardly to uncover the exhaust port l5 just as the latter comes into registry with the exhaust ports 35, the force of the explosion in the cylinder here being spent so that it is desirable to get rid of the gases of combustion at this point. This exhaust is of the usual two cycle type and is therefore not entirely completed before the upward movement of the cylinder il moves the ports 55 and 35 out of registry as shown in Fig. 5 and brings the intake poits d2 and 2i into registry. The latter takes place at a time when further downward movement of the piston, in conjunction with the cooling of the remaining gases of combustion, has produced a semi-vacuum in the cylinder chamber il above the piston. This results in a. gaseous fuel mixture furnished through the intake pipe 22 being sucked inwardly past the valve 23 and through the passage 2t and ports 2i and t2 into the cylinder chamberl l.

The rising of the cylinder il cuts off the intake ports 2l and "i2 and the compression stroke Vwhich is shown in progress in Fig. 6 now takes place.

As the piston 5@ nears its uppermost position, the cylinder lll starts downwardly until the maximum compression stroke is arrived at approximately at the point illustrated in Fig. 7. Here it is seen that the ports d2 and 2i have again come into registry with the result that a small amount of compressed fuel is expelled through these ports into the passage 2i? which in engine design practice is made so small that the amount of compression lost by this is negligible. The valve 23 of course prevents passage of this fuel into the pipe 22. From the point shown in Fig. 7, the cylinder Il and piston 5@ both move downwardly only a short distance before the ports i2 are shifted out of registry with the ports 2i and the port i3 is brought into registry with the spark plug port 3i at which time the spark plug res the charge of fuel compressed in the upper end of the cylinder chamber 4l thus initiating another cycle of operation similar to the one just described.

What I claim is:

l. In an internal combustion engine, the combination of a cylinder having intake and exhaust ports communicating therewith; a piston in said cylinder; a reciprocal head forming a combustion chamber in said cylinder between said head and said piston; a crank shaft having primary and secondary cranks thereon; means connecting said primary crank with said piston and said secondary crank with said reciprocal head, said cranks being so related as to cause said piston and said reciprocal head to move relatively apart during the power stroke of said piston; means for opening and immediately closing said exhaust port when said combustion chamber has expanded to substantially three-fourths of its greatest volume; and means for opening said intake port when said combustionvchamber has expanded to substantially its greatest volume.

2. A combination as in claim l, in which the throw of said secondary crank is substantially one-half that of said primary crank and in which said secondary crank is positioned substantially ninety degrees ahead of said primary crank.

3. in an internal combustion engine, the combination of: a block having a bor-e formed therein, said block including intake and exhaust ports communicating with said bore; a cylinder reciprocal in said bore and having intake and exhaust ports formed in the wall thereof for registration with the intake and exhaust ports of said block; a head provided on said cylinder; a piston reciprocal in said cylinder, said piston and said head forming a combustion chamber in said cylinder; a crank shaft having primary and secondary cranks thereon; and means connecting said primary crank with said piston and said secondary crank with said reciprocal cylinder, said cranks being so related as to cause said piston and said reciprocal head to move relatively apa-rt during the power stroke of said piston, the exhaust port oi said cylinder moving into and out of registration with the exhaust port of said block when said combustion chamber has expanded to substantially three-fourths of its greatest volume, said intake port of said cylinder moving into and out of registration with the intake port of said block when said combustion chamber has expanded to substantially its greatest volume.

4. A combination as in claim 3, in which the throw of said secondary crank is substantially one-half that of said primary crank and in which said secondary crank is positioned substantially ninety degrees ahead of said primary crank.

WALTER T. KNSLOW. 

